WordNet
progressive vaccinia
n. a severe or even fatal form of vaccinia that occurs mainly in persons with an immunological deficiency; characterized by progressive enlargement of the initial lesion [syn: vaccinia gangrenosa]
Wikipedia
Progressive vaccinia
Progressive vaccinia (also known as "Vaccinia gangrenosum," and "Vaccinia necrosum") is a rare cutaneous condition caused by the vaccinia virus, characterized by painless, but progressive, necrosis and ulceration.